Power Automate (WDL) function

mod — Power Automate (WDL) function reference

Remainder after division.

Syntax

wdl

mod(dividend, divisor)

wdl

mod(17, 5)

→ 2

A common pattern for alternating logic or batching every other item.

wdl

equals(mod(variables('rowNumber'), 2), 0)

→ true / false

wdl

equals(mod(item()?['Index'], 100), 0)

→ true every 100th item — useful for a periodic checkpoint

mod() by zero throws the same as div() by zero — validate the divisor first.
The result takes the sign of the dividend for negative numbers, so mod(-7, 3) returns -1, not 2, which differs from the mathematical modulo some people expect.

From Math